I will never know just how close I came to being on the bus that exploded in Tavistock Square.

What I know for certain is that I was riding on a London Transport double-decker on the same route only minutes before the explosion. At the time, I thought I was safe. My miscalculation could have been a fatal mistake.

Even as I stepped from the train at King's Cross at 9am, two of the bombs that would cause so much misery had already detonated. The first explosion had torn a train apart at Liverpool Street station, the second had gone off at 8.56am in the King's Cross Underground station, below my feet.

Blissfully unaware of what was happening, I made my way to the underground, where I was greeted by harassed staff stopping passengers going to the platforms below.

At that point, the official story was disruption caused by a power surge.

I saw masses of people surging to the entrance, but they seemed to quickly disperse on the orders of London Underground staff, and I guessed they had migrated to nearby Euston.

But the first signs that things were terribly wrong came as I made my way along the street and police cars converged on the station. Officers jumped out and began cordoning off Euston Road, one of London's central routes.

Mindful of the fact that the underground may not be safe, I took what I thought to be the wise decision to catch a bus.

My route to the High Court would take me past Russell Square then on to Tavistock Square.

I wasn't scared. This was London. The problem, whatever it may have been, was all underground.

In a moment, everything changed. Normally distant and unapproachable Londoners grabbed each other and cried: "What's happening?"

Others hugged each other and I overheard them saying: "I'm scared."

I stood by the side of the road watching convoys of ambulances, police and Special Branch officers screech past.

The Red Cross, NHS training teams and specialist fire crew quickly followed. An NHS Blood Transfusion team was close behind.

This was no power surge.

Tourists and Londoners alike grabbed their mobile phones, desperate for news, but the network was down.

One passer-by ran past shouting to anyone listening: "Don't get buses or tubes, this is serious."

It all happened so fast. At 10.26am, more ambulance and fire crews tore along Kingsway to the heartland of destruction.